I am looking at getting Runebound second edition soon but I'm a bit confused on the products available. Are all the expansions playable in second edition or are they for first edition only?

The expansions are for R2E; none of those listed are for R1E. Many of the small box expansions are now out of print and you will need to shop around for them. Big box expansions are still widely available. Look to the Runebound 2E page on BoardGameGeek.com for a complete list at a glance.

For some of the small box stuff you might look to TimeWellSpentGames.com as a starting point in your search. Big box stuff can be found here at FFG or at Amazon.com

If you're interested on a good deal (andin the US)  I have a consolidated "Very Good" Runebound collection. I'm clearing space/saving up to buy MORE FFG stuff! Here's the link to my BGG marketplace entry:

http://boardgamegeek.com/geekstore.php3?action=listallforsale&recent=&sortby=name&startletter=R&quick=&pageID=41

And my description (price is TOTALY negotiable):

Runebound (Second Edition) $100.00

[Make Offer]
[Market Info] Titeman (2)

Includes the following expansions: Avatars of Kelnov, Beasts and Bandits, Crown of the Elder Kings, Cult of the Rune, Relics of Legend, Rituals and Runes, Sands of Al-Kalim, The Cataclysm, The Frozen Wastes (with new replacement board,) The Scepter of Kyros, The Seven Scions, Traps and Terrors, and Weapons of Legend. Pictures available on request.

All expansions combined into base game box and four seperate cardboard card boxes (Adventure Packs divided between 2 200 card boxes; the rest in a 550 box.) Some pieces sorted into Plano box. Everything in really good condition, some box wear. Will only sell as an entire set...

@titeman

All that for only 100

FYI I sold my set...